CN-121985716-A - Perovskite film layer, preparation method and solar cell

Abstract

The invention relates to a perovskite film layer, a preparation method and a solar cell, wherein the preparation method comprises the following steps of coating a modified perovskite precursor solution on the surface of a substrate, and annealing to obtain the perovskite film layer; the modified perovskite precursor solution comprises methyl urea. According to the invention, the methyl urea is added into the perovskite precursor solution, so that the perovskite crystallization can be regulated under the condition of not leaving gaps by utilizing the unique molecular structure and chemical property of the methyl urea, thereby avoiding the problem of performance reduction caused by the gaps, improving the light capturing efficiency of the perovskite film layer, enhancing the uniformity of electric field distribution in the device and improving the overall performance of the solar cell.

Inventors

• Chen Koucheng
• LI ZIJIA
• HE CHENXU
• WANG SHUMAO

Assignees

• 正泰新能科技股份有限公司

Dates

Publication Date

20260505

Application Date

20260203

Claims (10)

1. 1. The preparation method of the perovskite film layer is characterized by comprising the following steps of: coating the modified perovskite precursor solution on the surface of a substrate, and annealing to obtain the perovskite film layer; the modified perovskite precursor solution comprises methyl urea.
2. 2. The method of claim 1, wherein the amount of methyl urea in the modified perovskite precursor solution is 0.5mol% to 0.7mol% of the perovskite material.
3. 3. The method of preparing according to claim 1, wherein the solvent of the modified perovskite precursor solution comprises a combination of dimethylformamide and dimethyl sulfoxide.
4. 4. The preparation method according to claim 3, wherein the volume ratio of the dimethylformamide to the dimethyl sulfoxide is 3:1-5:1.
5. 5. The method according to claim 1, wherein the annealing temperature is 140 ℃ to 160 ℃; And/or the annealing time is 15-25 min.
6. 6. The method of manufacturing according to claim 1, wherein the method of coating comprises spin coating.
7. 7. The method of any one of claims 1-6, wherein the perovskite material in the perovskite precursor solution comprises a halide perovskite material.
8. 8. The perovskite film layer is characterized by being prepared by the preparation method according to any one of claims 1-7.
9. 9. The solar cell is characterized by comprising the perovskite film layer of claim 8 or the perovskite film layer prepared by the preparation method of any one of claims 1-7.
10. 10. The solar cell according to claim 9, wherein the solar cell is a perovskite crystalline silicon stack cell.

Description

Perovskite film layer, preparation method and solar cell Technical Field The invention belongs to the technical field of perovskite batteries, and relates to a perovskite film layer, a preparation method and a solar cell. Background Perovskite materials have great application potential in the fields of photovoltaics, optoelectronics and the like due to excellent photoelectric properties. In recent years, the photoelectric conversion efficiency of single junction perovskite solar cells has been significantly improved, and laboratory certification efficiency has exceeded 27%. In addition, perovskite materials have also made important progress in the application of light emitting diodes, photodetectors, lasers, and other optoelectronic devices. Currently, perovskite materials are mainly studied in terms of improving performance stability, optimizing device structure, developing low-cost preparation process and the like. Among these, the quality of crystallization is considered to be one of the key factors affecting the properties of perovskite materials. High quality perovskite thin films generally have larger grain sizes, higher crystallinity, and lower defect state densities that can effectively suppress non-radiative recombination, thereby improving the photoelectric conversion efficiency and long-term stability of the device. In the research of wide band gap perovskite solar cells, additive engineering is widely applied to improve the morphology and crystallization performance of thin films. For example, sodium poly (p-styrenesulfonate) (PSS) has been demonstrated as a commonly used additive to significantly enhance the crystallinity of wide band gap perovskite films and reduce the defect state density, thereby inhibiting the phase separation problem of mixed halogen perovskite films. Similarly, in perovskite/heterojunction stacked solar cells, the impact of interface design and material selection on device performance is particularly critical. Research shows that the deposition of the high-quality perovskite absorption layer can be realized by optimizing the textured structure of the surface of the silicon wafer and the interface of the intermediate Transparent Conductive Oxide (TCO), so that the overall performance of the laminated battery is improved. Therefore, the intensive research on the crystallization regulation mechanism of the perovskite material has important significance for promoting the application of the perovskite material in high-efficiency photovoltaic and optoelectronic devices Although perovskite materials represent a great potential in the photovoltaic field, poor crystalline quality often causes a series of performance problems such as reduced efficiency, reduced stability, and reduced device lifetime. In particular, the large number of defect states present in perovskite thin films can lead to severe non-radiative recombination, thereby significantly reducing the photoelectric conversion efficiency of the device. In addition, the instability of perovskite materials under high temperature or high humidity environments is mainly due to defects and noncoordinating ions in their crystal structure. For example, prolonged high temperature annealing may lead to evaporation of organic cations and halides, leaving uncomplexed Pb 2+ or Pb clusters on the film surface, which defects not only affect carrier transport, but also accelerate the degradation process of the material. To overcome the above problems, it is important to adjust the perovskite crystallization process. By introducing proper additives or optimizing annealing conditions, the nucleation and growth processes of perovskite can be effectively controlled, so that the crystallization quality and stability of the film are improved. However, there are significant differences in the mechanism of action and effect of the different additives, so in practical applications it is necessary to select the appropriate additive according to specific requirements and optimize the conditions of use thereof. Therefore, adjusting perovskite crystallization is not only a key means for improving material performance, but also an important research direction for promoting the commercialization process of perovskite solar cells. The realization of conformal coverage of perovskite layers on special surface structures such as micron-sized silicon pyramids is another key technical challenge faced in the perovskite solar cell manufacturing process. The design of such structures is initially aimed at improving the light absorption efficiency by means of the light trapping effect, however, the complex geometrical morphology characteristics thereof put more stringent technical requirements on the deposition process of perovskite thin films. Aiming at the technical problems, development of a perovskite film layer which can improve the photoelectric conversion efficiency of a solar cell and can realize the conformal coverage of the perovskite film layer on th